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excited new owner!

Its official! Contract signed, deposit sent, Z8 coming, although not too soon.
Big thanks to the current owner for his help and willingness to work with me. The car is a late production 02 car with 12k on it. The seller is holding the car for me so we can fly out and use it for a two week trip revisiting my old childhood and teen year haunts in Michigan, including several old friends who live on the wonderful N. Michigan lakes (Torch and Burt). Also, the tail end of the trip will allow me to catch my high school reunion, which I am also looking forward to, as we had a very tight class.
Excuse my digressions! Back to the car. My first Z8, and set up as I would have done. Brembo BBK, Dinan stage II susp, Dinan software, Eisenmann exhaust, Quaife 3.64 differential, 20"HRE's and the very important BMW performance pack installed.
I have only drive the stock car so having these quality mods makes the whole wait all that much harder.
I look forward to joining some west coast drives and meeting some other owners.

One question I have is about the ride with 20" wheels. We have good but rough roads. Not many potholes but irregular patching etc. Not likely to get better given the economy and lack of funds. Are the 20's a sacrifice in handling and comfort?

Very big thanks to Mike and also to Jerry for his inspiration and enthusiasm for the model.

With the Dinan set up I would also suggest 19" would give you a little more safety bearing in mind the deteriorating roads and budgets. IMHO those wheels don't really suit the flowing lines of the car too well, so I think you will be in a win-win situation going an inch down. HRE make some gorgeous wheels that do look good on the Z8, I especially like these ones.

Andrew Macpherson

Expert Z8 Inspections, with full support for both Z8 sale and purchases.

With the Dinan set up I would also suggest 19" would give you a little more safety bearing in mind the deteriorating roads and budgets. IMHO those wheels don't really suit the flowing lines of the car too well, so I think you will be in a win-win situation going an inch down. HRE make some gorgeous wheels that do look good on the Z8, I especially like these ones.

Thanks guys.
I hear ya both on the 20's.
I like those too, in fact, through all the searching for the right Z8 I have kept a picture of a black car with those wheels with a background of aspens, I think its a swiss owner.
And yes, its James Blantons old car.

I have had those wheels on a pcar before and although I like them, too much cleaning time.

Congratulations- Very happy for you! I think the 890 series would look good on the Z8.

Here are my favorites

890R

I think these below could be better. One of the problems with wheels for the Z8 is if they have a hard edge to the star or other interior design elements they look kind of "thin" when viewed head on. If you note the OEM Z8 wheels have rounded elements to them. These don't have any openings in the star arms, and thus less places to look "thin"....

Its official! Contract signed, deposit sent, Z8 coming, although not too soon.
Big thanks to the current owner for his help and willingness to work with me. The car is a late production 02 car with 12k on it. The seller is holding the car for me so we can fly out and use it for a two week trip revisiting my old childhood and teen year haunts in Michigan, including several old friends who live on the wonderful N. Michigan lakes (Torch and Burt). Also, the tail end of the trip will allow me to catch my high school reunion, which I am also looking forward to, as we had a very tight class.
Excuse my digressions! Back to the car. My first Z8, and set up as I would have done. Brembo BBK, Dinan stage II susp, Dinan software, Eisenmann exhaust, Quaife 3.64 differential, 20"HRE's and the very important BMW performance pack installed.
I have only drive the stock car so having these quality mods makes the whole wait all that much harder.
I look forward to joining some west coast drives and meeting some other owners.

One question I have is about the ride with 20" wheels. We have good but rough roads. Not many potholes but irregular patching etc. Not likely to get better given the economy and lack of funds. Are the 20's a sacrifice in handling and comfort?

Very big thanks to Mike and also to Jerry for his inspiration and enthusiasm for the model.

I first drove mine last october. Congratulations great moments to come!

Hi, thanks all for the kind greetings.
I wanted to ask the 19" guys what size tires you are running? Do people keep with stock sizes or is there a better handling alternative in terms of stagger and/or profile?

As I mentioned, we are going on a journey and adventure in the car this summer and will post lots of pictures from that trip.
John

Hopefully GM will chip in here as he has a lot of experience with 19" trying different staggers and widths. I know he has done quite a bit of experimenting to neutralize the stock set-up's understeer with wheels, camera & swaybar settings, so I would wait for the word from him before settling on anything. Here is an older post about his set up.

Andrew Macpherson

Expert Z8 Inspections, with full support for both Z8 sale and purchases.

BMW's engineers believe a balanced weight distribution provides the best overall handling, so most of their high performance models come close to 50/50 front to rear weight distribution. This should provide a neutral driving experience (no tendency towards understeer and no tendency towards oversteer) with excellent vehicle dynamics however, in the interests of safety, BMW uses a front to rear tire width stagger to insure their cars exhibit inherent understeer without sacrificing the car's dynamic responsiveness. The Z8 falls into this category. If you like the way your stock Z8 handles at or near the limit, sticking with the OE f/r stagger is one option. In the case of 19" rims, that means running 245/40-19s up front and 275/35-19s in the rear. If Michelin PS2s are your preferred tire, they are available in these sizes. For some reason Tire Rack no longer lists the 275/35-19 size but I used them on my Z8 in the past and Michelin's web site says they are available so it may be an error of omission on the Tire Rack site. These tires will maintain your Z8's OE handling balance while improving its dynamics due to the increased grip provided by a stickier rubber compound and shorter sidewalls. Again, if you like the way your stock Z8 handles but would like to increase its cornering grip and acceleration capability, you can increase the overall width of the tires while retaining the same front/rear stagger by choosing 255/40-19s up front and 285/35-19s in back. Michelin PS2s are available in these sizes. In this case, the front tires are slightly taller than the OE tires so your Z8's front end will be slightly higher and the rear tires are also slightly taller, so the rake angle will be essentially unchanged. A side benefit is that the taller rear tires will make your speedometer more accurate. One important thing to consider, if you go this route, is that these wider tires require wider rims. In the case of the 255s, rim width should be between 8.5-10" and for the 285s, rim width should be between 9.5-11". Fitment of front tires on the Z8 is somewhat limited by the suspension design, with minimal clearance available on the inside, so wheel offset is critical when installing wider wheels and tires. If your Z8 is running at stock ride height, outside clearance (fender well lip) shouldn't be a problem. If your car has been lowered, you must be very careful about outside clearance since the tires may rub when the suspension is compressed. Increasing negative camber will alleviate some of this concern. Aesthetically, keeping the outer edges of the tires within the arches is usually preferable so be careful with offset choice here, too. And remember, when you are comparing wheel offsets, if your new rims are wider than the OE rims, you must compensate for that extra width when making the comparison. In the rear, wheel offset is far less critical in terms of clearance since there is lots of room, inside and out, for wider wheels and tires to fit. Most people feel that the rear OE offset leaves too much space between the outer edge of the tires and the fender well lip so this is a place where you can use your offset choice to compensate. An alternative is to use wheel spacers to shift the offset towards the outside. One other thing to keep in mind as you play with wheel options: Depending upon the wheel offsets you end up with, you may alter the front or rear track of the car. This is the measurement between the centers of the front pair of tires and the centers of the rear pair of tires. Because of the Z8's particular clearance issues described above, it is difficult to increase the front track measurement but easier to do this in the rear. Keep in mind that if the ratio of front to rear track is altered from the OE specs, handling will be affected. Generally, an increase in front track will result in an increase in oversteer while an increase in rear track will result in an increase in understeer. If you have to make undesirable tire/wheel/offset choices due to the constraints discussed above, you can use an adjustable anti-roll bar to compensate for unwanted handling changes: stiffer/shorter front bar increases understeer, stiffer/shorter rear bar increases oversteer.

If you aren't happy with the OE handling of your Z8 at the limit and would like to reduce its tendency towards understeer, you can again use adjustable anti-roll bars to dial in the handling to your liking and/or you can alter the front to rear tire stagger to affect a change. By narrowing the stagger, you will increase your car's front end grip relative to the rear and dial out some of the understeer in the process. This is one of the main ingredients in Steve Dinan's BMW handling packages (he strives for zero stagger!). On a Z8, one approach would be to run 255's up front and stick with 275's in the rear. Aesthetically, you would definitely need to increase the track in the rear, either by wheel offset or the use of wheel spacers, so the overall impact on handling will be lessened if you take appearance into consideration. An alternative approach, which is what I am running on my driver Z8, is to use 265/35-19s up front and 285/35-19s in the rear. This reduces the f/r stagger while still allowing an increase in rubber at the rear, which helps with appearance as well as providing better traction during acceleration. The problem with this approach is that you may encounter clearance issues up front and the only way to overcome them is with the combination of offset/wheel spacers and significantly increased negative camber. I am running wheel spacers and custom made negative camber plates although my car has been lowered via the ACS suspension kit.

If you never drive your Z8 anywhere near its limits, you can essentially ignore all of the above mentioned handling concerns and just fit whatever tires and wheels you think look best, assuming they will fit. Most people would probably go as wide as possible, particularly in the rear, although available 295s tend to be substantially shorter than the OE tires which means the rear of the car will be lowered relative to the front end (not a good thing in terms of aerodynamics) and your speedometer readings will be highly optimistic. Since you can use adjustable anti-roll bars to compensate for some of the handling changes brought about by tire choice, there is some merit to this approach.

Finally, there is the option of installing 20" wheels and tires (ala Alpina Roadster V8) and in this case, the tire choice would be 255/30-20 up front and 285/30-20 in back. Keep in mind that the car's rake will be increased with this combination since the front tires are significantly shorter than the OE diameter, so ground clearance up front will be reduced. I don't recommend using 20" wheels and tires on a Z8 unless you install the PP and the full Alpina suspension kit. Otherwise, the amount of impact forces directed into the front suspension could cause structural damage to the chassis. Besides, 19" wheels and tires will be lighter, thus reducing critical unsprung weight, and there are far more performance tire choices available in 19" sizes than in 20".

One final point: when selecting tires, remember to look for their load index and speed rating. They should be the same as or higher than the OE tires' ratings to be safe. Where performance is the primary consideration, I would opt for a higher rating, particularly in the load index where you may find SL and XL options available. XL versions have stiffer sidewalls. Unfortunately, as with most things relating to a car's handling, you must be careful not to upset the balance either you or the factory are seeking so running SL at one end and XL at the other may not be the best choice.

Freudian slip!

Originally Posted by macfly

Hopefully GM will chip in here as he has a lot of experience with 19" trying different staggers and widths. I know he has done quite a bit of experimenting to neutralize the stock set-up's understeer with wheels, camera & swaybar settings, so I would wait for the word from him before settling on anything. Here is an older post about his set up.

GM,
Thanks for yet another concise, clearly written and easily understandable synopsis.

Could you please comment on the use of spacers and their relative safety with regard to width. I have read that they can be unstable but have never found a suitable explanation. I am going to fit my car with rear spacers but have held off on the purchase as I am not entirely sure about the size (10mm, 15mm,..).

If you use high quality wheel spacers coupled with the correct length lug bolts (very important), there will be no stability or safety issues. The Z8 has hub-centric flanges which insure proper alignment of the wheel when mounted on the hub. Properly designed wheel spacers will use those flanges to insure their own alignment and then provide their own hub-centric flange to insure proper wheel alignment. Unfortunately, this only applies to spacers 10mm or thicker. Less than that and there isn't enough material to provide a proper hub-centric flange. Having said that, I have used 5mm spacers on my Z8 with no problems. You do have to pay more attention when mounting the wheels to insure proper alignment but some of the original flange will protrude through the thin spacers to help with this. I use studs instead of lugs which makes the whole process much simpler. Most wheel spacers are made from an aluminum alloy to keep their weight down but that means they are subject to electrolysis when mounted on a steel hub. To avoid them becoming "welded" onto your hub, be sure to coat them with a thin layer of anti-seize compound when first installed. Also, make sure you clean your hubs with a wire brush to insure the spacers seat flat against the mounting surface. Also, count the number of OE lug threads extending beyond the wheel's mounting surface and make sure your new lugs are long enough to provide an equal number of threads when spacers are included. Particularly in the rear, be careful not to use lugs that are too long since they will interfere with the hub's ability to rotate by protruding into the parking brake mechanism which is inside the hub. It should be pointed out that the use of wheel spacers does put more strain on the wheel bearings but unless you are going above 50mm, this really isn't an issue. The same is true for wheels whose negative offset moves the outer edge of the wheel outboard of the OE position. While wheel spacers may seem like a compromise on a high performance automobile, keep in mind that Porsche uses wheel spacers on a regular basis to allow fitment of their various wheel on different models. In my experience, 10-15mm spacers in the rear is right where you want to be so I suggest ordering both sizes and seeing which you prefer.

GM, thanks for the reply regarding wheel/tire sizes. I have only driven stock sizes before. The car I just bought has 20" HRE's on it and I am likely to go to 19", mostly for ride comfort and unsprung weight. I do have the Dinan adjustable sway and the perf. pack fitted. I like the idea of the increased rubber, less understeer set up you are running. I also have brembos but from what I understand, they are compact and will cause little adverse fitment issues, although I have not confirmed that personally yet. I need to get the model number or some specific measurements to confirm this.
The other issue that will carry importance for my particular driving needs is weight. I would like to see an overall decrease in wheel/tire weight, certainly over the 20's and hopefully over the stock set up as well.
Can you speak to the specific wheels you have tried and if you were able to feel a difference in driving dynamics with the lighter wheels?
BTW, I pm'ed you once, after reading your musings from years back. We share the same Michigan, Aspen, Montana connection, which is a pretty rare progression for sure. thanks, John

The Brembos will not fit under OE Z8 wheels but most 19" wheels should provide adequate clearance. Having the Dinan adjustable anti-roll bars will allow you to fine tune the handling of your Z8 regardless of your wheel/tire choice, so you are in a good position to experiment. Reducing unsprung weight (those parts of a car not supported by its springs) will yield the biggest benefits of any weight reduction you can undertake on your Z8 and reducing the weight of wheels and tires yields the biggest benefit of any unsprung weight reduction, so you're definitely looking in the right area. The reason lighter wheels and tires makes such a big difference is because you not only get a reduction in unsprung weight, which means your suspension will be much quicker to react to direction changes along with imperfections in the road surface, you also get the maximum possible reduction in rotational inertia because the weight savings occur at the greatest distance from the axle, which means your car will accelerate and decelerate faster. Lighter rotors also help but not as much. In terms of handling, if the weight reduction is significant, you will definitely notice a difference in street driving as your Z8 will be more stable on bumpy roads and it will react more nimbly to direction changes. The unseen benefit is that you will reduce the amount of impact transmitted by the suspension into your Z8's chassis and as we all know, this is a very desirable thing.

I am running 19" BBS RGR wheels shod with Michelin PS2s and the combination makes a huge difference in the way my Z8 performs. To put this in context, the OE wheels and tires weigh 62 lbs. up front and 67 lbs. in back, while 19" BBS RGRs with equivalent width PS2s weigh 45 lbs. in front and 49 lbs. in back. I am a big fan of BBS wheels and if you like the way they look, I can't think of a better way to go. I do use spacers with them on my Z8, but that is a matter of taste, not necessity. The 265/35-19 PS2s I'm running up front require custom made camber plates to fit on a Z8 without clearance issues so I think the 245/275 or 255/285 combos are a more practical choice for most people and then just dial in the handling you prefer via the anti-roll bars.

There are lots of wheel/tire choices out there for the Z8 and as long as you achieve a weight reduction, I don't think you can go wrong. Have fun!

Congrats on the z8 Riverflyer!

I have modified my Z8 slowly and noticed gradual improvement in overall suspension handling and dynamics but the most noticeable gains came initially with the dumping of the run flat tires and then again when I upgraded to the 20" Michelin PS2s on 20" Beyern rims.

I decided on the Type 5 Beyern primarily due to ease of fitment as they are made to fit BMWs and the 20mm offset is identical to the stock offset of both the 18" OEM and 20" Alpina wheels. They are also readily available and cheap enough to replace if they get damaged (one disadvantage of anything custom or ultralight wheel such as the HREs) and the entire wheel / tire combo I have still weighs less than the OEM set up with a modest decrease in unsprung weight on all 4 corners.

I too have rough roads here in Oklahoma but find that the Dinan suspension combined with the 20" tires and wheels make for a great ride, comfortable on the highway and around most of the roads around town and make for great handling around the Ozark twisties or the local track. I had the Dinan suspension way before the wheels and ran it with both the OEM wheel / tire combo and without the run flats on Stock wheels (had SO3s) but without the PP, and did not sustain any frame damage. GMs comments are dead on target but I do not think you have to have the full Alpina suspension if you have 20 " wheels in order to prevent frame or shock tower deformation. I had the Dinan suspension for at least 20,000 miles with stock wheels and runflats without sustaining damage and I have known several Z8 owners with stock suspension and 20" wheels and no runflats who did not sustain damage either. It is thought that the caster plates of the Dinan set up (which is where BMW got the plate idea for the PP as I understand it) is what is thought to be protective, especially when you get rid of the unsprung weight of the OEM runflats.

I personally think the decision between the 19" or 20" is just a matter of taste and therefore get what you like. Unless of course your like Macfly -- and you just change your wheels every year cause you want too!! Hmmm, stock, BBS, then Hamann 20" and now BMW Motorsport 20" -- what will be next?

Its cool to see the longevity many of you have had. I rarely keep a car very long, hope this is an exception. Maybe its partly a search as I feel I have a couple of keepers presently, just took me a while to find them.

Hmmm, stock, BBS, then Hamann 20" and now BMW Motorsport 20" -- what will be next?

I think next will be 19" for sure, and I am really liking the M5 rims everyone is doing, but I may search once more for ultimate lightness. I wish HRE did a prettier version of their lightweight Competition rims.

Andrew Macpherson

Expert Z8 Inspections, with full support for both Z8 sale and purchases.

I also run 19 HREs 255/40 in front and 295/35 in the rear. I wanted the same (or close) front rear stagger and the width and sidewall height maximized. It works very well for my driving style and the poor road conditions up here.

Sorry for the less than "Andrew quality" picture

Nice car BTW

2000 Red over black
heavily modified for performance. Although, not to the level of GM's car

I also run 19 HREs 255/40 in front and 295/35 in the rear. I wanted the same (or close) front rear stagger and the width and sidewall height maximized. It works very well for my driving style and the poor road conditions up here.

Sorry for the less than "Andrew quality" picture

Nice car BTW

2112, thanks for the feedback and compliment. I found a custom set of BBS rims in 20" but have also decided to stay with 19". I have a factory fresh set of HRE 447's that were for an e46 m3 and am waiting to hear back from Vince as to the cost to retrofit to the z. I think the rears are ok so it may not cost too much.

If anyone wants a set of 20" Hre 541, as pictured in the beginning of the thread, please email at [email protected]
thanks

C90s look like perfect combo of looks and lightness

Andrew, I agree completely about the possiblilities with our silver/black cars. And, as you know, these wheels (which look almost like the beautiful 540s) are light as well -- if I am counting right they beat the very light 540's by almost 3 pounds, and 540Rs by 4 pounds! Assuming that HRE doesn't mind me quoting them (since I am spreading the word), I quote their reply to my question about relative weights:

John,Exact weights are difficult since we can have an almost infinite number of back pad heights to accommodate custom fitments. As a baseline, a C20 for a 997 Porsche GT3 RS weighed in at 20.2lbs for a 19x8.5? and 24.4 lbs. for the 19x12?. The C90?s come in around .5 - .75 lbs lighter depending on the setup. The 540 will come in around 22.5 and the 540R about 23.5.

Andrew, I think you should immediately order and mount. Can't wait for your pics.

What about a wheel collection?

Andrew,

We have noticed your Imelda tendencies. Admit it, wouldn't you like to photograph the new Topaz car with the M Sports? And then try C90's with brushed centers and polished rims? Just hang'em on the wall, like a shoe rack.

In my opinion the most important criteria we should take in to consideration is the looks of the wheels on our cars rather than technical aspects like weight.
The wheels should not look like aftermarket or we should not put any other BMW`s stock/standard wheels. Like M5 wheels. Because they become identical with these cars.
M6 wheels work fine but Motorsport wheels are the only wheels which suit best on the Z8.

I agree and the Z8 is a car that is actually pretty difficult to just put any wheel on.

River, I think you might have found a keeper in the Z8. Its just a very special car. If you ever begin to think "oh, Ill just trade it for this..." go drive it and then tell me you didn't change your mind. The car is just special plain and simple.

I think Im liking the E60 M5 wheels the best for the Z8, aside from the OEM wheels of course.

Another Excited New owner

I hate to start new threads when there is one that might be best for it, and this looked like the right one to post my Z8 finally arriving from CA. My greatest thanks again to Marty Wiener (havenhurstkid). I could not have found anyone more helpful and generous with their time in guiding me to the successful purchase. Also Matt and Dana at Peter Pan who were simply outstanding in working with me. They are as picky as any owner in getting the car right. So here are the pix from Passport Transport pulling up to the getting her in the garage with my beloved 1983 320i daily driver since new. I will post lift details in the lift thread.

Hey Tom,
Big congrats. Wonderful cars, as you well know by now.
I am jealous that you get curbside delivery. For me its a 20 to 50 miles drive to meet transport, depending on the truck. The reason being super twisty mountain roads, so of course the drives home are very memorable...

Thanks for all the good wishes, and I do hope to get that top off soon. Took my first drives today. Not far, but enough to realize that its more than a "go fast" car. Cool day, windows down, seat heaters on. My wife and I were cruising behind a slow car when the light turned yellow. I think she was surprised when I was able to switch lanes and get through the light ahead of the other car. I pushed the sport button once...oh my, lots to look forward to experiencing.

Ten years later, and every drive in the Z8 is as exciting as the first drive. This is the only car I can say this about, but then again it is the car I keep for those great drives, so ! guess it makes sense, especially as I love great drives! ;-)

Next year looks like our next major group drive, so as soon as we get everything confirmed with the Club, and of course with the organizers at the Monterey Car Week we'll get onto doing the plans.
It's shaping up to be a Northern California loop starting in San Fran > Napa > Humbolt > the Redwoods, the Klamouth River, maybe Crater Lake if we can figure out the booking, then return via Shasta, Lassen, maybe Thunderhill and Napa to Monterey. I'm expecting something like a weeks drive ending up with the last four days of Car Week in Monterey.

Andrew Macpherson

Expert Z8 Inspections, with full support for both Z8 sale and purchases.

Congratulations, and thanks for the post/photos. Every time I read about someone's delivery and first ride, I get to re-live my memories from 8 years ago. Hang on because each ride gets even better, especially when you meet up with the Z8 group for an adventure. And its great to see another Z8 in TX!! I'd bet that we're catching up to California in numbers of cars.

It's shaping up to be a Northern California loop starting in San Fran > Napa > Humbolt > the Redwoods, the Klamouth River, maybe Crater Lake if we can figure out the booking, then return via Shasta, Lassen, maybe Thunderhill and Napa to Monterey. I'm expecting something like a weeks drive ending up with the last four days of Car Week in Monterey.

Any chance a Z8 owner-in-waiting living in Sonoma can join in (with an AM V8 Vantage, so there is at least a Henrik Fisker tie-in with the Z8)?!

It?s the same car I looked at my dealership 8 years ago but didn?t buy, because I didn?t want to sell my Z8 with loss and cancel the order for the M3 CSL. The car comes from the first owner with 45,000 miles and is stratusgrey with black interior.